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arXiv · 1201.4471

A Realistic Treatment of Geomagnetic Cherenkov Radiation from Cosmic Ray Air Showers

Klaus Werner·Krijn D. De Vries·Olaf Scholten
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Abstract

We present a macroscopic calculation of coherent electro-magnetic radiation from air showers initiated by ultra-high energy cosmic rays, based on currents obtained from three-dimensional Monte Carlo simulations of air showers in a realistic geo-magnetic field. We discuss the importance of a correct treatment of the index of refraction in air, given by the law of Gladstone and Dale, which affects the pulses enormously for certain configurations, compared to a simplified treatment using a constant index. We predict in particular a geomagnetic Cherenkov radiation, which provides strong signals at high frequencies (GHz), for certain geometries together with "normal radiation" from the shower maximum, leading to a double peak structure in the frequency spectrum. We also provide some information about the numerical procedures referred to as EVA 1.0.

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Klaus Werner, Krijn D. De Vries, Olaf Scholten. 2012-01-21. A Realistic Treatment of Geomagnetic Cherenkov Radiation from Cosmic Ray Air Showers. https://doi.org/10.1016/j.astropartphys.2012.07.007

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